A polyether diol is a compound which is widely utilized for various applications. The polyether diol is generally a compound having a hydroxyl group at each of both terminals of an oxyalkylene chain. The compound is obtained by polymerizing ethylene oxide or propylene oxide. 2,2-Dialkyl-1,3-propanediol to which ethylene oxide or propylene oxide is added is also known as a modified polyether diol. As an example of the applications of the modified polyether diol, Japanese Patent Application Laid-Open No. 2008-19260 discloses an agrochemical composition; Japanese Patent Application Laid-Open No. 2000-219557 discloses a concrete additive composition; and Japanese Patent Application Laid-Open No. 10-7622 discloses a resin composition or the like.
Conventionally, a method for subjecting 2,2-disubstituted-1,3-propanediol to ring-opening addition of ethylene oxide or propylene oxide is well known as a method for producing a modified polyether diol having a 2,2-disubstituted-1,3-propanediol skeleton (hereinafter, referred to as a “neo skeleton”). While on the other hand, examples disclosing a method for producing a polyether diol including only a neo skeleton are scarce. One of the examples is disclosed in Bulletin de la Societe Chimiquede France (1967), (8), 2755-2763. A method for obtaining di-neopentyl glycol from neopentyl glycol is disclosed as a method for producing a polyether diol by an intermolecular dehydration reaction using an acid catalyst in Bulletin de la Societe Chimiquede France (1967), (8), 2755-2763. A method for producing another polyether diol having a neo skeleton is disclosed in Acta Chemica Scandinavica vol. 45 (1) p 82-91 (1991). A method for simultaneously obtaining di-neopentyl glycol and tri-neopentyl glycol from 3,3-dimethyl oxetane is disclosed as a method for producing a polyether diol by a polymerization reaction of an oxetane compound in Acta Chemica Scandinavica vol. 45 (1) p 82-91 (1991). Furthermore, a method for producing other polyether diol having a neo skeleton is disclosed in U.S. Pat. No. 3,287,419. A method for obtaining 3,3′-oxybis-(2,2-dimethyl-1-propanol) (hereinafter, sometimes referred to as di-neopentyl glycol) from 2,2-dimethyl-3-hydroxy-propionaldehyde and 3,3′-oxybis-(2-ethyl-2-butyl-1-propanol) from 2-ethyl-2-butyl-3-hydroxy-propionaldehyde is disclosed as a method for polymerizing 2,2-dialkyl-3-hydroxy-propionaldehyde using an acid catalyst to provide a polymer, and thereafter reducing the polymer to produce a polyether diol in U.S. Pat. No. 3,287,419.
In the meantime, a reaction for reductively ring-opening a cyclic acetal compound having a 1,3-dioxane structure using a hydrogenation catalyst is known as a method for producing an ether compound containing a hydroxyl group. Specifically, the following producing method is disclosed. That is, a method for hydrogenating a substituted 1,3-dioxane compound using a catalyst containing a Group IB metal in the Periodic Table and an acid carrier to produce a 3-alkoxy-propane-1-ol compound is disclosed in Japanese Patent No. 2977782.